Skeletal System (Skeletal system/tissues (Red & yellow bone marrow…
Support, assistance in movement, protection, mineral storage, blood cell formation, energy storage
Major structural components
35% organic bone tissue (bone, connective tissue, cells, ex. matrix, collagen), 65% inorganic - minerals, fibrocartilage, hyaline cartilage, articular cartilage
Compact bone & spongy bone char.
Compact - on every bone, perforating canal, periosteum (dense irregular) Spongy - osteocytes, ex. martix, no osteons, in sections of long and flat bone, endosteum (layer)
Components of long bone
Epiphysis w/ epiphyseal line, articular cartilage, compact bone (w/ periosteum), diaphysis (shaft), medullary cavity (marrow, lined w/ endosteum), periosteum
Red & yellow bone marrow
Red bone marrow - gelatinous, soft tissue. Yellow bone marrow - adipose tissue
Red bone marrow - blood cell formation. Yellow bone amrrow - nutrient storage
Types of bone cells
Osteogenic (stem) cells - (periosteum and endosteum), osteoblast - (create ex. matrix), osteoclasts - (endosteum)
Where two bones meet, short interconnecting fibers. Suture - skull only, no movement. Syndesmosis - D.R.C.T, little movement, distal tibiofibular. Gumphosis - tooth meets alveolus, immovable, periodontal ligaments
Synchondrosis - hyaline cartilage, between 1st ri and manubrium, epiphyseal plates. Symphysis - pubic symphysis and intervertebral joints (fibrocartilage, hyaline cartilage). Slightly movable.
Movable joints. Joint capsule with inner (areolar CT) & outer layer (D.I.C.T). Joint cavity filled w/ synovial fluid (lubricating, shock absorber, nourishes articular cartilage).
6 types of synovial joints
Gliding movement, intercarpal and intertarsal joints, joints b/w vertebral articular surfaces
Flexion and extension, elbow joints and b/w phalanges
Rotation, radius and ulna, atlas C1 and C2 joint
Flexion and extension, adduction and abduction, metacarpophalangeal (knuckle) and wrist joints
Flexion and extension, adduction and abduction, only in thumbs
Flexion and extension, adduction and abduction, rotation, shoulder and hip joints
Produce movement, open/close body passageways, maintain posture and stabilize joints, generate heat
Contractility - myofilaments, shortening of muscle cells. Excitability - nerve signals which stimulate muscle cells. Extensibility - stretching. Elasticity - stretch and recoil.
Connective tissue layers
Epimysium - surrounds the outer layer of skeletal muscle (D.R.C.T). Perimysium - "around the muscle", fasicles. Endomysium - Within a fascicle.
Components of skeletal fiber
Myofibrils - Unbranched cylinders, contain myofilaments which contract protein. Mitochondria - Supply energy for muscle contraction. Sarcoplasmic reticulum - Smooth ER which surround each myofibril. T tubules - Deep invaginations of the sarcolemma that run b/w terminal cisterns.